Asymptomatic syndrome of inappropriate secretion of antidiuretic hormone (SIADH) following duloxetine treatment for pain with depression: Two case reports.

BACKGROUND

Syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is a common side effect in patients treated with SSRIs and venlafaxine, while there is little information on SIADH in the treatment of duloxetine for pain.

CASE PRESENTATION: The patients were an 83-year-old Japanese male and a 71-year-old Japanese female. Several years earlier, they complained of pain. Accidentally, blood tests revealed hyponatremia of 110 mmol/L and 108 mmol/L 35 days and 40 days after initiating duloxetine 20 mg/day, respectively. The hyponatremia of both patients recovered after switching from duloxetine to mianserin.

CONCLUSION

We conclude that asymptomatic SIADH was induced by use of duloxetine. Psychiatrists should be aware of this syndrome.